I recently purchased a 1997 Rav4 (3F-SE Engine) with 162000 miles. Overall, it is a great car. The only problem (besides a clutch, which can wait) is that it hesitates/bucks between 1500-2100 rpm while accelerating. This happens usually on a shift change from 1st to 2nd, or while in 2nd and after decelerating to make a turn. This only happens after the engine has warmed up, i.e. the temp gauge is above 25%. When cold, there is no hesitation at all. It just passed emissions testing. Check engine light is off. I recently replaced the TPS (and adjusted it properly), with no change in symptoms. This car does not have a MAF sensor.

Since you know the clutch is near the end of its life, could it be just that the clutch is slipping a tad at this speed and shifting time? Does it seem like that? Or is it definitely an engine problem?

Clutches don’t slip at a particular speed. When a clutch is bad it’ll slip greatest with the least amount of pressure on it (i.e. when the clutch is just being engaged). They don’t engage fully…then start to slip.

No, definitely engine missing. Too lean momentarily, then it kicks in smooth (maybe from O2 sensor corrections). It sounds exactly like when I forget to open the petcock on my motorcycle and it bogs down until I open and then the engine recovers instantly. Also, it runs perfect until temp gauge is up to about 25% - which wouldn’t be the case with a slipping clutch.

Interesting! I have a 2004 Rav4 with only 50000 miles that is doing the same thing (and mine is automatic, so no clutch). It just started recently, so I’ve assumed it just needs a carb adjustment. I notice it when I start back up from a light, for instance. it sort of hesitates at a certain rpm, then kicks in. I’m afraid that hesitation could cause an accident if I’m merging with traffic. I never thought about it before, but it’s true that it doesn’t happen when the car is cold, only once I’ve been driving for a bit, so temp may be a factor.

Just a wild guess, but my Corolla would hesitate, but only when accelerating going uphill at about 35 mph. It turned out to be the spark plug gap had widened over time to become out of spec. New plugs fixed the problem.

I have a 2002 rav 4 with 97,000 and love it! Your issue sounds more like its in the "brain of the car. When the computer goes bad, everything starts to be affected. Had this happen to me and it was like the car was falling apart. Don’t believe you have a carb as now days everything is fuel injected. Toyota has had a lot of issues, and the computer is one of them. Have your rav 4 hooked up to a diognostic tool for the brain.